<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>MVVM Demo</title>
</head>

<body>
  <div id="app">
    <h1>{{msg}}</h1>
    <input type="text" v-model="value.a">
    <p>{{value.a}}</p>
  </div>
  <script src="./js/demo.js"></script>
</body>

</html>